build: fix compiler version detection

Compiler version tuples should be numeric for tuple comparisons
to work.

Also correct check for AIX where the minimum supported GCC is 6.3.0

PR-URL: nodejs#24879
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
(cherry picked from commit c3dd0d0)

configure.py

@@ -584,8 +584,8 @@ def try_check_compiler(cc, lang):
 
   values = (to_utf8(proc.communicate()[0]).split() + ['0'] * 7)[0:7]
   is_clang = values[0] == '1'
-  gcc_version = tuple(values[1:1+3])
-  clang_version = tuple(values[4:4+3])
+  gcc_version = tuple(map(int, values[1:1+3]))
+  clang_version = tuple(map(int, values[4:4+3])) if is_clang else None
 
   return (True, is_clang, clang_version, gcc_version)
 
@@ -659,6 +659,8 @@ def check_compiler(o):
   ok, is_clang, clang_version, gcc_version = try_check_compiler(CXX, 'c++')
   if not ok:
     warn('failed to autodetect C++ compiler version (CXX=%s)' % CXX)
+  elif sys.platform.startswith('aix') and gcc_version < (6, 3, 0):
+    warn('C++ compiler too old, need g++ 6.3.0 (CXX=%s)' % CXX)
   elif clang_version < (3, 4, 2) if is_clang else gcc_version < (4, 9, 4):
     warn('C++ compiler too old, need g++ 4.9.4 or clang++ 3.4.2 (CXX=%s)' % CXX)
 
@@ -823,6 +825,15 @@ def configure_mips(o):
   o['variables']['mips_fpu_mode'] = options.mips_fpu_mode
 
 
+def gcc_version_ge(version_checked):
+  for compiler in [(CC, 'c'), (CXX, 'c++')]:
+    ok, is_clang, clang_version, compiler_version = \
+      try_check_compiler(compiler[0], compiler[1])
+    if is_clang or compiler_version < version_checked:
+      return False
+  return True
+
+
 def configure_node(o):
   if options.dest_os == 'android':
     o['variables']['OS'] = 'android'